MT-ND2 and amyotrophic lateral sclerosis: In ND2 of whole blood samples (Fig. 4d), as well as in the D-loop region, COI and ATP8 in platelets (Fig. 4d–g; Kruskal–Wallis with Dunn’s correction for multiple comparison, *p ≤ 0.05, **p ≤ 0.01) of possible maternal versus non-maternally linked ALS patients, the number of heteroplasmic mutations is also increased.